Reflecting telescope



Sept. 25,1923. 1,468,973

R. W. PORTER REFLECTING TELESCOPE Filed Jan. 25. 1922 www I RUSSELL w. Poe-tuna, or srninerinnnvnanonrc.

REFLECTING TELESCOPE. 7

Application filed January '25, 1922. Serial to. 531,526.

To all whom it, may concern: 4 Be it known that I, RUSSELL M Ponrnaa citizen of the United States,,res1c ung .if oringfield, in the county of'l ilindsor and .ctale of Vermont, have invented new and useful improvements in Reflecting Telee:

scopes, of which the following is a specificaion.

ride a telescope for terrestrial and celestial observation of such character that it may be manufactured and sold at a reasonablepr ce,

mat it may be capable of standing the rela'-. ours and none professionals.that it may be mounted pertively rough usage of ama-i manently upon a pier or support so not to require placement before or removalafter use, and that it will lend itself to ornamental treatment so that it may form a pleasing ture of a garden.

()n the accompanying drawings, illustrated an embodiment of the invention which meets these several objects.

Figure l represents the telescope in side elevation with the parts adj ustcd ior celestial observation in the zenith.

Figure 2 represents a fFODlLQlEViliLlOD of the same.

Figure 3 represents a sectionon the line 3-3 of Figure 2. r Figure 4 represents a plan view partially in section with the parts adjusted so that the reflecting mirror is in aplane substantially.

parallel with the plane of the hour circle.

The telescope, which I have illustrated as embodying my invention and which is hereinafter des ribed more in detail, comprises an ocular, a concave paraboloidal mirror,

they maybe removed and placedin a case for safe keeping from the weather.

The optical arrangement is a modification of This invention has for its object to pro- 1 hai ethe NewLonianand Herschellian types, the prism or. silvered diagonal and thelaterally projecting ocular'ot Newtons telescope being. retained, and the concave reflecting gmirror being less .displaced'than in the Herschellian telescope, so as to, bring the ocular and. the diagonal closer. together. 'The'tubes of bothsaid types oftelescope are dispensed-f with, andthe ocular and prism are sup ported-by a standard or blade arising'froml one side of that element of the'mounting on. which therefiecting mirror is supported,

On the'drawings, I have shown at '10 the upper portion of pier, which may be built in permanent form of masonry, brick or 7 Concrete; 1 whichthe telescope is mounted.

and on which is supported and'securedby any suitable means a base plate 11. r 12 is held upon the base plate bya threepoint support; To this end the base is see cured to the base plate by a bolt 13 at its rear, there being in additiontwo supporting abutment screws'14, 15 which pass through lugs or brackets on the base and rest upon the base plate as shown in Figures 1 and 2. Prefer aloly the base, surrounding the bolt 13, is provided with a convex boss' 16 between which and thebase plate there is placed complemental washer or collar 17. A collar 18, whoselower end is rounded, is arranged between the nut 131 and the bolt and the bottom 0% the socket 19in which the collar 18 is placed. it will be readily seen that, by loosening the nut 131 and adjusting either or both of the screws 14: and 15, the base be adjusted to accurate position. i

The base 12 servesto support a hollow member of the mounting which for con venience 1 term a, bell;i .This bell substantially semi-spherical in shape, except that its rear wall is cut away orrernoved. In line with its axis it is provided with a pivot or trunnion 20 which is seated in a thrustsocl ret or hearing Ql formed on the base 12 so that the-bell is capable of being moved about its axis. Inasmuch ,as the mounting-is equatoriah'the axis movement of the bell is coincident with the polar axis, being in Figure 3 approximately at an angle of 45 thehorizontal. fllhis bell" is likewise supportedat three peints {that is,

A base it is supported by the trunnion 20 and bearcrably there is a hemispherical member 28 which rules the s oport V for the reflecting mirror and wi '1 which the ocular and prism or diagonal connected to move bodily therewith. 'Preler bly this member is solid and provided with trunnions 529 which are journaled in the hollow hemispherical shell or bell. the s of these trunnions constitutin the of declination. The member ided with socket to receive the dal; concave mirror 30 which pretis of glass. The socket may be termed by a continuous or an interrupted l o interrupted flangecomprising the three upwardly projecting; lugs equally spaced from each other and having their inner faces coincident with a circle whose diameter is equal to the outside diameter of the reflecting mirror. The mirror preferably rests upon three equally-spaced adjusting screws so that the optical axis of the m rror may be adjusted. Rising "from the rear side of the member 28, or bowl as I may term it. there is a blade or standard which rigid therewith. The upper end of the standard is turned forwardly and is so termed at its extremity as to provide a bearing 32.. In this hearing there is removably journaled a spindle 35 having at its lower end a head 36 which supports both the ocular and the prism or diagonal. The ocular, which is indicated as a whole at 37, supported by an arm 38 projecting late, lly from the head 36. The diagonal, which is indicated conventionally at 39, is supported in a shell el-O formed on or secured to the head 36 and having an open-' ing in its side through which the bundle of ligh rays may pass to the ocular. Of course the ocular and the diagonal are arranged at the proper focal distance from the concave mirror, the length of the standard or blade being determined by the focal lenogth oi" the mirror and the distance between the ocular and the prism or diagonal. The upper end 0? the spindle projects hevond the bearing 34 and is provided with a threads-"l end on which there is a knurled nut ell. Between this init and the end or" the bearing thereis placed preferably a compression spring; 4-2 which holds the head 36 trictionally and tightly against the lower end of thebearing so as to maintain the inay be desired. I have shown any arm 38 in any position to which it may be adjusted about the axis of the spindle, which of course is coincident with the optical axis of the mirror or reflector. I

The mirror is very slightly displaced, so that its optical axis diverges, in the direction of the ocular, from the axis of the bowl on which it is mounted.

From the'description thus tar given, it

is quite apparent to those skilled in the are that the telescope may be trained upon any ob ect or body, either terrestrial or celestial, by swinging the bell about the polar axis, i. e. about the axis of the pivot 20, and by moving the bowl or member 28 about the axis of declination, i. e. about the axis of the trunnions 29.

The bell isv provided with a fiat rim or flange 4E3upon which is marked the hour on the bell is secured an index or pointer 46. Provision is thus made whereby the telescope may be set on any celestial object by taking the proper qualities from the ephemeris or nautical'ahnanac. After adjusting the telescope to the proper declinae tion about the declination axis as indicated by the index or pointer 46, it may be clamped in that position. To this end, the bowl is clamped to the bell by the clamping screw 47, thus providing a large leverage for holding the bowl securely to the bell. After the telescope is clamped in declination, the instrument may then be moved in right ascension by rotating either or both of the rolls 23, 24;. For this purpose, the spindles on which the rolls are securee are provided wit-lrknurled knoll... by which they may be rotated. The observer may, by the rotationof one or the other 0'? the rolls, overcome the diurnal lllCLlOll ot the earth and hold any celestial object in the center of the field of view.

One of the advantages of a mounting such as I have described is that the primary mirror 30, whichconstitutes the principal weight, lies between the hearings or trunnions of the declination axis and midway above the three points of supportwhich are so located that lines drawn from the center of weight of the moving parts thereto form (in the latitude of Springfield, Vermont) an almost perfect tetrahedron, thus providing a compact, solid and rigid construction.

suitable not only for small instruments but also for large ones where'the weightof the mirror is great. Another advantage of the coucentrio with the axis of the trunni-ous 29 n form of mounting is that it requires no additional weights for counterpoising. The bowl 28 and the standard or blade 83 are in equilibrium about the declination axis; and, by displacing the declination axis slightly toone side of the polar axis as shown in Figure movement thereot' about the declination axis.

The bell is preferably more or less in skeletonform so that it will not retain water.

All of the various parts of the telescope, with the exception of the optical train, may be cast in bronze or other durable metal so as to remain permanently mounted upon the pier without injury from the elements; They may be formed to present a highly ornamental or ornate appearance, and, if

desired, the rim of: the l ell and the crown of Y the base may be inscribed with the names of great'astronomers, signs of the zodiac,etc

The telescope as herein described has all of the means necessary. for adjusting the optical train and bringing" the; polar parallel to that of the earth for all positions between the 35th and the th parallels of north latitude. This,'as has been stated, may be accomplished by releasing the nut ot the screw 13 and adjusting the screws lei and 15. The optical axis of the concave mirror may be adjusted by means of any one of three screws Provision is also made, as has already been described, for turning the eye-piece and the prism about the optical axis oi the mirror so that one may observe at any convenient or oesired angle. Not only is the telescope adapted for use on celestial objects, but, by reason of its mounting, it may be trained upon terrestrial ob jects as well. lVhen used in observing celestial objects, it may, with the aid of the hour circle and the declination scale, be trained upon such object and then. caused to follow the object by the rotation of one or" the supporting rolls for the bell.

In order to prevent scattered light from entering the-eyc-piece or ocular when the telescope is used for terrestrial observation in daylight, aremovable tapering shield is telescoped or otherwise attached to the shell 4.0, as shown in Figure 1. For night work. this shield may be easily removed.

It is apparent that my invention is capa' ble of m 7 different embodiments. and'that many changes may be made in the particular embodiment of the invention herein shown and described without departing. from the spirit and scope of the invention as defined in the claims.

recast a .Having.thus'explained the nature of my I said invention and described a way of making and using the same, although: without attempting to set forth allot theforms in which it may be made or all of the modes of its use, what I claim is':-+ 1. An astronomical, reflecting comprising a reflector, a'prisni or diagonal telescope I r and a laterally arranged ocular, in combina tion with a support for the reflector capable olimovement about the polar axis and-"the declination axis and a stand d rigidly connected with and extcndingnpwardly from said support and having the ocular and prism or diagonal mounted at its free end.

25A reflecting 'telescope comprising paraboloidal reflector, 'a tilting support therefor, a standard or blade extending from one side oii'said support in direction. longitudinal of the optical of. said 'reflector, a prism or diagonal mounted on said standard or blade and intersectingsaid "spa:

cal axis, and an ocular mounted on said arm or blade in optical'relationto said prism'or' V diagonal. i y 1 3. A reflecting telescope comprisinga sup" 1 port having pivots or trunnions by which it 7 may be hungn. standard or blade arising from one side thereof and having a bearing:

at its free end, a parabolo-ida'l reflectonon said support, a member journaled in said bearing; with its axis coincident with the optical axis of said reflector, an ocular on said member arranged; transversely of said axis, and a prism or diagonal supportedby said member in optical relation to said re;

flector and said ocular. 1 H

4-. A; reilect ng' telescope comprising a hemispherical bowl or member having; piv-f nions for said support. and a member in i which said truunions are journaled.

6. A reflecting telescope. comprising apa-. raboloidal reflector, a solid hemispherical support having a socketfon its flat face to re ceive said refiectorya standard rising from one side of said support and supporting parts of they optical train at itsfreeend, and trunnions projecting laterally 'from said support. with'their axis displaced laterally from the optical axis of said refiectonand above the face of said support, whereby said support poised. p a

71A reflecting telescope comprising a and the parts" thereon arelequ'i f a paraboloidal reflector removably mounted thereon, a standard i iug from one side of the support, a moni r removably journaled in the free end or. said standard with its ax c :1: dentivith the optical axis of said rei ,ct-or and having; a laterally projectinc; a. n. ocular in the said arm, and prism or diagonal on said membe vnerebv said prism or diagonal and said ocular are 'able with said member lt'rom ictinsf telesc hcrical howl 7' "iden' v ii. a spindle jcurneled said bearing and ll, l I

' lT-f] said spindle. an 4 id arm. and means .\'l1lCl1 it is movaxis and the declinaabout the poi tion axis.

a solid hemiard rising telescope comprising s11. alt howl having a s from one side thereo; and supported on said bowl standard and comprising lrterally rranged ocular s pported bv said t to move about the optical axis of another member of the train.

10. A telescope comprising a base. a bell having an axial end thrust trunn on soclo eted in said base. and spaced rolls engraoingthe large end of aid hell.v whereby said bell is supported said base by a threepoint bearing. said hell having; an hour circle at its rim. a hemispherical support trunnicned on said bell to move about an axis transverse to the axis of said bell, and an optical train supported by said hemispherical support.

11. An equatorial telescope comprising a h e an adjustable three-point support for s.v rd base, hemispherical bell having. an axial end thrust trunnion socketed in said base spaced rolls engaging the larger end of the bell, said parts being arranged with the axis of said bell coincident with the polar axis, an hour circle on said bell, an index or pointer on said base associated with the'hour circle, a reflector, a support therefor trunuioned on said bell to move'about a declination axis and a graduated segmental scale and an index on said support and hel to indicate the angle of declination.

A equatorial telescope comprising a thereof, an optical train supported bv said bowl and standard a bell in which said bowl is mounted to move ahout an axis of declination and having an hour circle exteainp; about the rim thereof, and a base on which said bell is mounted to more about the polar axis and having an index assoc ated with the hour circle.

eoi'iatorial telescope comprising a having a standard risin from one side In testimony whereof I have ailixed my signature.

RUSSELL W. PORTER. 

